White House Press Secretary Jay Carney blasted Mitt Romney for his campaign's new television ad this afternoon, accusing the Republican presidential candidate of lying about President Barack Obama's position on welfare reform.

The ad, released this morning, lays out the Romney campaign's latest assault against Obama, which focuses on his administration's July directive allowing states to request waivers to get out of welfare work requirements.

“Under Obama’s plan, you wouldn’t have to work and wouldn’t have to train for a job," the ad says. "They just send you your welfare check. And welfare to work goes back to being plain old welfare.”

The White House disputed this characterization Tuesday, arguing that the directive is designed to give state's greater flexibility in administering welfare programs.

"This advertisement is categorically false and blatantly dishonest," Carney told reporters, noting that the waivers were most aggressively sought by Republican governors in Utah and Nevada, and that states are required to prove that their programs will put more people to work.

Carney also pointed out that Romney himself supported similar measures in 2005, when he joined other Republican governors in writing a letter to the Senate urging Congress to pass a bill that would have allowed states more flexibility in administering welfare.

"The hypocrisy knows no bounds," Carney said. "Perhaps his argument is with his past self, and I suppose that should not be a surprise."

It's worth noting that the governors were asking for action by Congress, not an executive order.

Texas Republican Senate candidate Ted Cruz took this line of attack during a Romney campaign conference call Tuesday, calling the directive "another action of executive arrogance."

"He didn’t try to make the argument to anybody that work requirements were unnecessary or were counterproductive in welfare," Cruz said. "Instead, he simply decreed it by executive order and this has been a pattern of this administration where they believe their own ideology trumps the views of the American people."

But the Romney campaign's memo on Obama's welfare position doesn't mention this line of attack, and Romney himself hasn't made that argument. Instead, he lavished praise on the 1996 bipartisan welfare reform bill passed under President Bill Clinton during a campaign rally in Illinois today, accusing Obama of trying to "reverse that accomplishment, by taking the work requirement out of welfare."

*An earlier version of this post incorrectly stated that the Romney campaign has not addressed the 2005 letter. That is incorrect. Deputy Policy Director Jonathan Burks told reporters on a conference call today that the letter was in reference to a Senate welfare reauthorization bill that increased welfare work requirements from 50% to 70% and increased state flexibility in administering the program.